Differential Diagnosis for Erythema Marginatum
- Single most likely diagnosis + Acute Rheumatic Fever: This is the most common association with erythema marginatum, a characteristic rash that appears as a pink ring on the skin, often seen in the context of acute rheumatic fever following a group A beta-hemolytic streptococcal infection.
- Other Likely diagnoses + Infectious Endocarditis: Although less common, infectious endocarditis can present with a variety of skin manifestations, including erythema marginatum-like lesions, especially in the context of certain bacterial infections. + Autoimmune Disorders (e.g., Lupus): Some autoimmune conditions can cause skin rashes that might resemble erythema marginatum, though the clinical context and other symptoms would typically distinguish these.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.) + Meningococcemia: This condition, caused by Neisseria meningitidis, can present with a rash that might be confused with erythema marginatum. It's critical to consider this diagnosis due to its high mortality rate if not promptly treated. + Rocky Mountain Spotted Fever: Another infectious disease that can cause a rash, though it typically has a distinct distribution and is accompanied by other symptoms like fever and headache.
- Rare diagnoses + Secondary Syphilis: Can cause a wide range of skin manifestations, including rashes that might be mistaken for erythema marginatum, though other symptoms and diagnostic tests would help differentiate. + Erythema Multiforme: A skin condition characterized by target lesions, which might be considered in the differential for erythema marginatum, especially if the presentation is atypical.